Tape reader



' NGV. 25, 1952 E o. BLQDGETT 2,619,532

TAPE READER Filed July' 12, 1950 6 Sheets-Sheet 1 /70 Z4 Z4 J 26 O o Z6 fg n ,J0

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/56 fio IN1/ENT?. 50W/N 0. M006 TT Nov, 25, 1952 1 y E. o. BLoDGEr-rl 2,619,532

' TAPE READER Filed July 12, l9 50 K 6 Sheets-Shee?. 2

ATTORNEY Nov. 25, 1952 E, Q BLQDGETT 42,619,532

' TAPE READER Filed July l2. 1950 6 Sheets-Sheet 3 FIGB.

lNvENToR .50W/fl 0. BLOGETT ATTORNEY Nov. 25, 19,52 E. o. BLOGETT 2,619,532

` TAPE READER Filed July 12. 195o 6 Sheets-Sheet 4 Q M IN V EN TOR.

EW//V 0 HODGETT YM/M Nov. 25, l1952 l E. o. BLODGTT TAPE READER Filed July 12. 1950 6 Sheets-Sheet 5 INVENTOR. [0W/N `0 ELODGETT MIM/M Nov. 25, 1952 E. o. BLODGETT 2,619,532

TAPE READER Filed July 12, 195o v Y e sheetsLsneet e f' d, f*

INVENTOR EDW//V 0. BLODGETT ATTORNEY Patented Nov. 25, i952 UNITED STATES PATENT oFFicE-i TARE, READER Edwin 0.` Blod'gett; Rochester, N; Y.; assigrnor to InternationalrBusiness Machines Corporation, NewYork; N: YI; a;l corporation ofNew-YorkHV Application J uly j12,,1950,jSerialN0. 173,320.l

3 Claims.

Thisl inventionrelates t`o-a :device rer-:reading-Y perloratedfrecord tapes, and Afor-'completing elec trical circuits in"accordancewith-perforations' in 1 such-f' tapes. i

Certain 'classes ofautoma-tic' accounting, cornputing and statistical machines utilize a-y controll data,- or -both',-f punchedrtherein- 'inrcoded/ form. Such tapesarereadin readingdevices ofithe'` class to-which-`thisinvention relates Yby means lof thattheyhavel operated onl such tapeiwith con-A siderable pressure.

Itis-therefore; anobjectof-ithis invention to provide* a tape' reading devicei which has perforation'reading pins thatoperate in a positive and certain. fashion, yet-with such'slight'jpressure on -thecontrol'tape thatall tape damage'as a result' of pin contactris' avoided'.`

It is a further object ofthe` invention' to provide a tape reading device which is under positivecontrol' ateajchrea'ding step.r To thisend there isprovidedcertain tape feeding and tape reading. latch mechanism under control ofr a single control" device, thereby insuring synchronous operationof'tape reading and feeding mechanism.

Other objects and'advantages of'the invention will'appear as a reading ofthespecication proceeds inY light of `'the drawings" in which:

Fig. lis a plane view ofthe tape reading mechanism';

Fig. 2"'is'a front; elevationalview ofthe tape reading mechanism with portions. broken away to show underlying structure;

Fig. 3 is a sideelevational view of the reading mechanism with portions broken away to show underlying .s structure Fig. 4' is a 'detail 'view of the, tapeY feeding mechanism;

Fi'g.v5' is a dtailiview of the controlmagnet and associated." control mechanism;

Fig: 6'is a detail view of. the., tape guidelmeans, reading pins and contact mechanism; and

Fig. 7 is a detail view of the tape run-.out con-` tact' and associated ycontrol mechanism.

Tape-controlled contacts As hereinbefore stated the invention relates to perforated tape, controlled circuit making and breaking mechanism,and accordinglyA there arel ineludedi a, ,plurality of paired. electrical contactsr iwhich `are disposed in opposite rows on asupr porting structure l2 which ismounte'd von'a base castingl. Inasmuch as the presentdevice is designed to sense any. one of. eight holes, or any: combination thereof,` in the control tape there.

are eight contacts under thecontrolnf tape per-'- forations anda ninth Acontact ,constitutingga tape` run-out..contact which will bedescribed in greater' detail hereinafter. Thecontacts in the opposite-v ly disposed rows arelarrangedon the supporting structure l2 in staggeredlrelatonso that they.

mayV bey individually controlled by interposeri mechanism which willbe more fully described' at a later point.

Each contact device .consists of a'xed! conducting strip It on one end of which is a ,Contactpoint, and a vresiliently .movable conducting strip' l 6 which carries. a `contact point in registration with the one. on the fixed strip |4"with which it" is paired. The resilient conducting strip IBjis' normally biased to close the contact points; Each contact device, however, isheld open, ex.

cept when a corresponding tape perforation` appears, by meansV of an offsety contact lever I8' which is mounted for limited. swinging movement on a pivot shaft'2 which forms partlof the supporting structure i2.` Each of thecontact levers I8 has a free end 22whi`ch when moved 'outwardlyj causes the contact operating end thereof to move outwardly. The contact operatingend of 'each lever hasrpivoted. thereto a short, outwardly eX-. tending projection 24 which is. notched to engage an upwardly extending section 26`fof .the..,asso. ciated resilient contact strips I6. As aresult of this structure, when the lowerfreeV ends 22lof Ithe contact levers I8 are moved outwardly the upper ends move outwardly, whereby the contact.

points on the associatedcircuit makerare opened. The contact levers i8 are guided in their movement by a pair of guide `combs 28', andthe,

nected by the contact lever bail `3l). One endof-v each strap is pivoted on the pivotshaft 20, and thev other end of each has mounted thereon a roller 36.' The contact lever bail assembliesare interconnected by a spring (not shown) wherebyA they are urged toward each other,.but.they arel kept in Anormally separated position by meansof interposer. bail studs 33 WhichfareA adapted4 to:

move between the rollers 36 at each end of the assembly. When the studs 38 are disposed between the rollers 36, the contact lever bail assembly is separated, the contact lever bails 30 are in contact with the free ends 22 of the contact levers I8, and as a consequence the contact points of the circuit makers are opened.

The studs 38 are carried by an interposer bail assembly 46 which in turn is pivoted on a pivot shaft 42. The interposer bail assembly 46includes a pair of spaced side arms 44 on the free end of each of which is located a stud 38 and from which it projects into position between the rollers 36. An interposer bail 46 interconnects the side arms 44 of the interposer bail assembly, and this bail is adapted to underlie and to control a series of interposers as will more fully appear hereinafter. Furthermore, the interposer bail assembly has attached thereto an interposer bail arm 48 by means of which the forwardly projecting arms 44 may be rocked about the pivot shaft 42 on which they are mounted. The free end of the interposer bail arm 48 has a cam follower 56 mounted thereon adapted to operate in contact with an interposer bail cam 52 when the interposer bail arm 48 is released from the influence of a control arm 54, as will be more fully explained hereinafter.

The operation of the tape controlled contact assembly is under the ultimate control of a series of interposer arms 56 and attached tape reading pins, one such arm being provided for each tape controlled contact lever. As best seen in Fig. 6 of the drawings the interposer arms 56 are freely pivoted on the shaft 42 on which they are mounted, and each consists of a lever having a pair of interposer shoulders 58 formed at the free end thereof. One shoulder 58 of each interposer arm will be associated with the free end 22 of its corresponding contact lever. In the inoperative or non-reading position of the device, the interposer arms will be positioned as shown in Fig. 6 of the drawings with one of its shoulders 58 in blocking or interposed relation with its associated contact lever. It will be seen, therefore, that even though the contact lever bails 36 are released, any contact lever whose interposer arm 56 is in blocking position will be restrained from movement and consequently its associated contacts will remain open.

Depending from each interposer arm is a reading pin 66 which is guided for reciprocating movement in a reading pin guide block 62. The path of the reading pins 66 intersects a tape feed throat 64 in the guide block 62. As a perforated 1 tape 66 is fed through the tape feed throat 64, the reading pins 68 are in light contact therewith by reason of the fact that each interposer arm 56 is under the influence of a light spring 68. The tension of the spring 68 is insuliicient to cause any damage to a control tape being read. However, the spring tension is sufficient to cause a reading pin 60 to enter a tape perforation in alig-nment therewith at the reading station. When this relationship is present the corresponding pin 68 will enter the tape perforation, causing the interposer arm 56 to swing on its Pivot shaft 42 sufficiently to withdraw the blocking interposer shoulder 58 from the path of its associated contact lever. Under these conditions when the contact lever bails 3D are moved inwardly away from the free ends 22 of the contact levers, a contact lever thus freed will move sufficiently to close its associated contact points. In the absence of a perforation in the tape, the

reading pins will rest lightly on the surface thereof, thus preventing the associated interposer arms 56 from moving out of the path of their associated contact levers, thereby blocking the levers against movement and avoiding the operation of their associated contacts. Whenever the interposer bail 46 is in its elevated position, the interposer arms 56 will be held in nonreading position. It will be noted in Fig. 6 that the interposer bail 46 underlies and is adapted to contact the bottom edge of the aligned interposer arms.

Control clutch 'I'he interposer arms 56 and consequently the reading pins 60 are retained in non-reading position by the interposer bail 46 until the interposer bail arm 48 is released by the control arm 54. Such release follows energization of a control magnet 16 (see Fig. 5) in connection with which operates an armature l2 which is pivoted on a stud shaft 14 and about which the armature may rock. The control arm 54 is likewise pivoted on the stud shaft 14. The armature l2 is a bifurcated structure having a laterally extending stop linger 16 adapted to limit its rocking movement about the shaft 14 by contact with an armature yoke 18. A second extension of the armature structure lies substantially parallel but in spaced relation in respect to the stop finger 16, and the free end of this latter extension mounts a cam following roller adapted to contact an armature knock-off cam 84. A spring 86 normally biases the armature l2 away from the core of the control magnet 16, but in order to render the action of the armature 'l2 positive in overcoming residual magnetism in the core El, the armature knock-off cam 84 is arranged to positively rock the armature away from the core immediately after the energizing impulses. The conjoint action of the control arm 54 and the armature 'i2 is achieved by the use of an interconnecting spring 88 (Fig. 1) and the relative adjustment of the two members is achieved through an adjusting screw 90 mounted in a flange of the control arm in such position as to contact the free end of the armature.

The interposer cam 52 and the armature knockoff cam 84 as well as a tape feed cam, as will appear hereinafter, are mounted for rotation with a power shaft 92 which is driven through a set of bevelled gears 94 from a, driven shaft 96. The driven shaft has a pulley 88 fixed to one end thereof for driving contact by vbelt |00, which is driven by a motor (not shown). The power shaft 92 and consequently the cams thereon are continuously rotated but tape reading operations are not performed until the control magnet 'i8 is energized. When an energizing current is present in the control magnet "IU, the armature I2 is attracted to the magnet core with the result that the Control arm 54 is rocked in a clockwise direction, thereby releasing the interposer bail arm 48. The interposer bail arm 48 is under the influence of a spring |62 (Fig. 1) which is effective to draw the cam follower 50 of the interposer bail arm into contact with the interposer bail cam 52. As the interposer bail cam 52 rotates, the interposer bail arm 4,8 rocks about the pivot shaft 42 and drops the interposer bail assembly 40. As a result of this action the interposers l56 are permitted to drop under the influence of their respective springs 68, and the reading pins 6U will enter any tape perforations that are presented in alignment with the.respectivesplns'.v When one ormoreof the pinsenters a perforation in` the tape,. the interposer 56 associated therewith drops sufficiently torfreeathe vinterposer shoulder 58r from blocking engagement. with its associated contact lever |8 so that when the interposer studs 38 move fromlbetween the contact lever bail rollers 3B, theacontactlevenor levers, thus freed of the interposer shoulders will move inwardlyunder that. influence of the.' resilient'. contact` strip |6 andpermit contacts of. such operated contact lever.v or levers, to close.

Asthe interposerbail cam 52 rotates and its highpoint rides in contact with the interposer bail. cam follower 50 the interposer bail arm assembly is rocked in a counterclockwise direc'- tion about its pivot'shaft.l 42 and the control arm `54 is moved inwardlyunder the influence of the* spring 88 (Fig. 1) so as tobe .in position torintercept the latch end of the interposer bail arm 48 asit rises, thereby holding it out of further contact with the interposer bail cam 52 and sustaining it against the influence ofthe spring |02. In this position the reading mecha- Tape feed The perforation in the tape are arranged in transverse rows that are equally spaced, and it is contemplated, therefore,y that as the tape is` moved through the reading throat 64 in step-by-stepprogression, the successive rows of perforations will present themselves at the reading zone in alignment with the reading pins.V For the` purpose of achieving a regulated feedingY ofthe tape through the reading zone there has been provided a tape feeding mechamsm which isv shown in detail in Fig. 4 of the drawings. to which reference may now be had. The tape.. is provided along its length withsprocket holes with which the teeth of a pin wheel.,|04.areadapted to: engage for feeding the tape.-l through the reading. throat 64. The pin wheel |,04.1is.V carried by ashaft |06 which is rotatedin'abearing'in. the support casting I3 by a..-feed;ra.tchet wheel |08.v The `feed ratchetwheel |002y has peripheral ,.teeth. which are periodically engaged `Joyafeed pawl ||0. for rotating the feed ratchet wheel as may berequired for the proper feeding ofthe tape.. The feed pawl I I0 is pivoted cna-stud I I2 carried. at one end of a feed pawl operating lever II4. The operating lever is mounted. on itspivot: shaft 42 for limited rockingamovement thereabout and it includes a feed pawl operatinggarm I |6;on the free end of which is mounted a cam follower ||8` adapted to contact atape feed cam |20 mounted for` rotation with-.thepower shaft 92. The feed'pawl operatlng. assembly. includes` a. transverse tape feed yoke |22 extending between the feed pawl operating arm VI I6:` and the. extension |24 to which the feedpawl` ||0 is attached. The feed pawl ||0 iszmovedthroughits feeding stroke by means of arelatively strong spring |26 which has one end thereofattachedfto the pawl and the other end thereof to apin |28 fixed in the support casting I8; appear; .thereforef that'I whenever the feed pawl operatingV assemblyl is. free-.to rock` about the pivot shaft 42. the end of the feed'fpawl I I0 will be forced into operating'engagement with the teeth of the feed ratchetwheel |08 under the influence of theoperatingspring |26.

A feed pawl stop |30 is carried by the feed pawl operating assembly extension |24 in such posi.- tion as. to limit the-:clockwise movement of the feedpawl. ||0. The support casing |3 carriesastop |32 whichis. positioned .to limit the countere clockwise movement of thefeed pawl I0'.v Be.- tween the two stops |30 and |32, thefeed pawl ||0 is therefore restrained to'. apredeterminedv path of movement as it functions to drive ythe feed ratchet wheel |08.

l'\.estorationv of the fed pawl ||0 to inoperative position-isV underthe influence of the tapev feed cam |20. When the tape. feed cam |20 rotates with its high point incontactwith its cam follower I I8, the feed pawl I I0 is withdrawn to its inoperative position.

Tape feed latch In order that the tape feed. mechanism maybe operative only whentape reading is desired; there has been provided a feed pawl latch |34 which is pivoted for rocking movement abouty a pivotshaft |30. The feed pawl latch |34 is urged tol rock about its shaft |36 ina counterclockwise direction under the influence of a spring 38, but the same is normally held against such rocking movement by one of the/.contact lever bails 32.

Pivoted on the feed pawl latch |34 is a .latch control lever |40 which has an extension .I 42vnormally adapted to lie in contact with oneof the contact lever balls 32. A spring |44 interconnects the feed pawl latch |34 and its vcontrol lever |140 so that clockwise movement of the control lever |40 imparted thereto by the contact lever bail 32 is transmitted to the feed pawl latch. Thefeed pawl latch has a hooked free end |46 adapted to engage under a shoulder |48 provided on the end of the feed pawl operating assembly finger |24.

It will appear, therefore, that as the feed pawl operating assembly is rocked into inoperative position under the influence ofthe tape feed cam |20, and as the contact lever bail 32 moves outwardly, the hooked end |46 of the feed pawl latch |34 will engage under the shoulder |48 andhold the feed pawl operating assembly in inoperative position. Upon the next succeeding tape reading operation the contact lever balls 32 will move inwardly, thereby releasing the` control lever |40 and permitting separation of the feed pawl latch |34 and the shoulder |48 under the `influence of the feed pawl latch spring |38. This will free the feed pawl operating assembly for a: tape feeding operation. The timing of the respective parts is such that the reading of the perforations in the tape by the reading pins 60 takes place during the first part of the cycle and the feeding of the tape takes place during the latter part of the cycle.

A fed ratchet wheel detent |50 is pivoted on the support casting |3 by means of a pivot screw |52, and it is rocked in a clockwise direction under the influence of a spring |54 so that a roller |56 on the free end of the detent arm is in contact with the teeth of the feed ratchet wheel |08, thereby providing a stabilizing inuencefor the rotary operation of the feed ratchet wheel and consequently its associatedtape feeding pin Wheel.

Tape run-.out control.

In order tov safeguard against they operation of the reading device in the absence of a tape there has been provided a tape run-out contact |60 which is solely under the control of a tape runout contact lever |62. The supporting strips for the contacts |68 are mounted in fashion similar to the tape controlled contacts, and the tape runout contact lever |52 is pivoted on the pivot shaft 28. During the normal operation of the machine the contacts |85 are closed as shown in the full line position in Fig. 7 of the drawings. The free end of the tape run-out contact lever |62 has a stud |64 extending laterally therefrom, and this stud lies in the path of the inner end |66 of an angular tape run-out arm |58 which is mounted for rocking movement about a pivot screw |16. The outer end of the tape run-out arm |68 has a laterally disposed finger |12 which in the normal operation of the device is adapted to rest on the inner surface of the tape at a point just beyond the tape throat 64. While supported by the tape, the tape run-out arm 68 is retained in such position that the inner end |66 of the arm merely bears against the tape run-out contact lever stud |64. 'I'he tape run-out arm is, however, springbiased in a clockwise direction so that in the event of tape failure by reason of breakage or because of exhausted supply, the tape run-out arm willI be rocked in a clockwise direction a sufficient distance to move the lower end of the tape run-out contact lever |62 in a counterclockwise direction to break the tape run-out contact |68. The tape run-out contact |69 may be in the main control circuit, and thereby upon opening thereof prevent further operation of the reading device until the tape supply has been restored.

In order that the tape may be held in cooperative relation with the pin wheel |84, there has been provided a tape hold-down arm |14 which has an arcuate surface |16 disposed in proximity to the pin wheel |84 and which serves the purpose of holding the tape in contact with the feed pins of the pin wheel.

In order that threading of the tape may be facilitated, the tape hold-down arm |14 is pivoter for rocking movement on its pivot shaft 42. By virtue of the pivotal mounting of the tape holddown arm, it may be rocked away from the pin wheel |84 into the dotted line position shown in Fig. '7, thereby exposing the pin wheel to facilitate threading of the tape thereabout.

It is, of course, desirable that the tape run-out contact be opened and retained in open position while the tape hold-down arm lle has been rocked away from the pin wheel |05, and to the end that the contact |59 may be opened and held against inadvertent closure during tape threading operations, there has been provided a camming surface |16 on an inwardly projecting portion of the tape hold-down arm. The camrningr surface |18 is so disposed in relation to the tape run-out contact lever stud |64 that rocking thereof, as in the open position of the tape hold-down arm, it will contact the stud |54 and move the lower end of the tape run-out Contact lever |64 in a counterclockwise direction, thus opening the contacts |69.

In order that the tape hold-down arm be somewhat positively held in both its open and in its closed position, there is provided a spring loop |18 which has one end thereof attached to a stud Si! r' extending from the face of an extension finger |82 forming part of the tape hold-down arm assembly. The other end of the spring loop is attached to a stud |84 fixed in and extending from the base casting I3. When the tape hold-down 8 arm is in its closed position, as shown in full lines in Fig. '7, the spring bow 18 exerts a counterclockwise force against the extension finger |82 and thereby moves the arcuate portion |16 of the tape hold-down arm against the pin wheel |04. When the tape hold-down arm is swung into the open position, as shown in dotted lines in Fig. 7, the spring bow |18 tends to force the extension finger |82 in a clockwise direction, thus tending to hold the tape hold-down arm in its open position.

It will appear from the foregoing, therefore, that the tape controlled contacts I8 are permitted t0 close when a tape reading pin 68 associated with a Contact lever I8 enters a perforation in the tape The aggregate force of the resilient contact strips I6 is considerable, and it will follow from the foregoing description and explanation that the interposer structure sustains this force and avoids transmission thereof to the reading pins; even though the reading pins are the ultimate control instrument for the pin controlled contacts, there is only the weight of the pin, its interposed nger and the force of the interposer spring 68 imposed on the reading pin 60 with the result that the reading pins offer no obstruction to the even passage of the tap-e through the reading zone. The tape may consequently be used repeatedly without fear of damage or undue wear by contact with the reading pins.

An effort has been made to describe the operation of the various subcombinations of the reading device as the description thereof proceeded. It is believed, therefore, that a summary description of the operation has been rendered unnecessary.

Having thus described my invention, I claim:

1. In a reading device for perforated control tape, a circuit maker including a spring contact effective when unrestrained to close its circuit, a pivot shaft, a control lever for said spring contact mounted between its ends on said pivot shaft for rocking movement thereabout, a connection between one end of said control lever and said spring contact, a control lever bail mounted on said pivot shaft for normally holding said control lever in circuit opening position against the tension of said spring contact, an interposer mounted at one end thereof for movement into and out of blocking relation with said control lever, a perforated tape reading pin mounted at the other end of said interposer, means for moving said pin into a tape perforation whereby said interposer is moved out of blocking relation with said control lever, an interposer bail assembly mounted for rocking movement into and out of restraining relation with said control lever bail, an interposer restoring bail carried by said interposer bail assembly, a continuously rotating cam for rocking said interposer bail assembly about its mounting, a latch for holding said interposer bail assembly out of operative contact with said cam, and means for releasing said latch Whereby said cam is rendered effective to rock said intei-poser bail assembly.

2. In a reading device for perforated control tape, a plurality of circuit makers each including a spring contact effective when unrestrained to close its circuit, a pivot shaft, a control lever for each of said spring contacts mounted between their ends on said pivot shaft for rocking movement thereabout, a connection between one end of each of said control levers and a related spring contact, a common control lever bail mounted on said pivot shaft for normally holding said control levers in circuit opening position against the tension of said spring contacts, an individual interposer mounted at one end thereof for movement into and out of blocking relation with each of said control levers, a perforated tape reading pin mounted at the other end of each of said interposers, means for moving said pins into tape perforations whereby their related interposers are moved out of blocking relation with their associated control levers, an interposer bail assembly mounted for rocking movement into and out of restraining relation with said control lever bails, a common interposer restoring bail carried by said interposer bail assembly, a continuously rotating cam for rocking said interposer bail assembly about its mounting, a latch for holding said interposer bail assembly out of operative contact with said cam, and means for releasing said latch whereby said cam is rendered effective to rock said interposer bail assembly.

3. In a reading device for perforated control tape, a pair of spaced oppositely disposed circuit makers each including a spring contact effective when unrestrained to close its circuit, a pivot shaft, a control lever for each of said spring contacts mounted between their ends on said pivot shaft for rocking movement thereabout, a connection between one end of each of said control lever and a related spring contact, a control lever bail for each of said control levers mounted on said pivot shaft for normally holding said control 10 levers in circuit opening position against the tension of the spring contacts connected thereto, an independent interposer mounted at one end thereof for movement into and out of blocking relation with each of said control levers, a perforated tape reading pin mounted at the other end of each of said interposers, means for moving said pins into tape perforations whereby said interposers are moved out of blocking relation with their associated control levers, an interposer bail assembly, common control means on said interposer bail assembly adapted to contact said control lever bails for operation thereof, means mounting said interposer bail assembly for rocking movement into and out of restraining relation with said control lever bails, an interposer restoring bail carried by said interposer bail assembly, and means for rocking said interposer bail assembly about its mounting.

EDWIN O. BLODGETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,895,110 Sundberg Jan. 24, 1933 2,391,984 Lake Jan. 1, 1946 

